I just brought the adventure and the mirage peddle system makes a knocking noise ( sounds like the fins are hitting the underside of the kayak). Spoke to the dealer and he said it is a problem with this model only.

I have tested the other models and none of them have the knocking noise.

Perhaps the drive is not full inserted? Does the drive itself have a click when operated outside the boat? Perhaps try the system on dry land to see where it is coming from? Drives sometimes rock fore and aft, but normally sit forward when in use. Are the pedals hitting something?

Hey aussi,
Welcome to the Hobie Forum and congrats on your new BigA! A knocking noise, huh--that's sounds like a new one! Make sure nothing is caught by the flippers (piece of seaweed, fishing line, etc.) that might be slapping up against the hull. Otherwise, check out Matt's suggestion. If your Mirage drive is not anchored firmly in the well with the cams, something like this might happen. Twist the cams at least 180 degrees to lock the drive in place. Also, as Matt suggested, work the pedals while holding the drive in your hands to see if the noise is reproducible out of the boat.
Best,
Dick

Hmmm, that's pretty interesting aussi. However, you may just be putting too much power to the pedals that are not adjusted correctly. As Dan suggested, try using the plastic adjuster handle to reset the pins and move the pedal shafts further forward to the next notch to increase the throw of the Mirage drive. That way your legs wil be extended more and there would be less chance that your pedal stroke would cause the flippers to slam up against the hull. If that doesn't do it, try the next notch further forward. Let us know if this works. Mebbe you have just been working out too much, and are a pedaling brute?

If the drive is fully seated into the well and all of the contact points are in correct position. Odd, but as Apalach said, you could be hitting the end of the stroke hard if the pedal shafts are set too far aft. Your leg should get full extension on each stroke and that eases or even prevents the fins from hitting the hull bottom at the end of a stroke. Here is a little gif animation on the adjustment of the pedal shaft position... we have had people that own Mirages and don't know that the pedals are adjustable...

You don't need full strokes for top speed. Even quick fluttering of the fins is fast.

I tested an Adventure today and actually heard knocking noise too. The noise would only occur when in a hard turn and it was not the pedals. Sounded like a cable inside the hull. Maybe his knocking noise is a cable or something inside the hull.